Neuroanatomy and sex differences of the lordosis-inhibiting system in the lateral septum
نویسندگان
چکیده
Female sexual behavior in rodents, termed lordosis, is controlled by facilitatory and inhibitory systems in the brain. It has been well demonstrated that a neural pathway from the ventromedial hypothalamic nucleus (VMN) to the midbrain central gray (MCG) is essential for facilitatory regulation of lordosis. The neural pathway from the arcuate nucleus to the VMN, via the medial preoptic nucleus, in female rats mediates transient suppression of lordosis, until female sexual receptivity is induced. In addition to this pathway, other regions are involved in inhibitory regulation of lordosis in female rats. The lordosis-inhibiting systems exist not only in the female brain but also in the male brain. The systems contribute to suppression of heterotypical sexual behavior in male rats, although they have the potential ability to display lordosis. The lateral septum (LS) exerts an inhibitory influence on lordosis in both female and male rats. This review focuses on the neuroanatomy and sex differences of the lordosis-inhibiting system in the LS. The LS functionally and anatomically links to the MCG to exert suppression of lordosis. Neurons of the intermediate part of the LS (LSi) serve as lordosis-inhibiting neurons and project axons to the MCG. The LSi-MCG neural connection is sexually dimorphic, and formation of the male-like LSi-MCG neural connection is affected by aromatized testosterone originating from the testes in the postnatal period. The sexually dimorphic LSi-MCG neural connection may reflect the morphological basis of sex differences in the inhibitory regulation of lordosis in rats.
منابع مشابه
Sex difference in septal neurons projecting axons to midbrain central gray in rats: a combined double retrograde tracing and ER-immunohistochemical study.
Sex difference in the number of neurons projecting axons from the lateral septum (LS) to the midbrain central gray (MCG) that are concerned with the lordosis-inhibiting system was investigated by injection of Fluoro-Gold (FG), a retrograde tracer, into the rostral MCG on the right side in male and female rats. Immunohistochemistry for ER-alpha and -beta was also performed with or without combin...
متن کاملInvolvement of Median Septum Region in Ghrelin Effects on Morphine-Induced Memory Impairment in Passive Avoidance Learning
Background and purpose: Many studies have reported the effect of morphine on memory impairment. Evidence suggests that ghrelin enhances memory consolidation. The median septum also has a major role in memory and learning mechanisms. The present study aimed at investigating the role of median septum on the effects of ghrelin in morphine-induced amnesia. Materials and methods: In this experiment...
متن کاملThe septum modulates REM sleep-related penile erections in rats
Rapid eye movement sleep in males is characterized by penile erection along with EEG desynchronization, muscle atonia, ponto-geniculo-occipital waves, and rapid eye movements (REM). The central neural mechanisms regulating sleep related erections (SREs) are not known. Recently, the lateral preoptic area has been shown to contribute in sleep-related erectile mechanisms. The present study was con...
متن کاملManagement of the Lateral Walls in Crooked Nose
In crooked noses, the lateral walls are different in shape and symmetry. Although the septum is very important to obtain a straight nose, identical and symmetrical lateral walls are needed for a straight looking nasal dorsum. As well as the septum, lateral walls also contribute in nasal skeletal support and stability. Thus, obtaining identical and symmetrical lateral walls is important. In orde...
متن کاملThe septum modulates REM sleep-related penile erections in rats
Rapid eye movement sleep in males is characterized by penile erection along with EEG desynchronization, muscle atonia, ponto-geniculo-occipital waves, and rapid eye movements (REM). The central neural mechanisms regulating sleep related erections (SREs) are not known. Recently, the lateral preoptic area has been shown to contribute in sleep-related erectile mechanisms. The present study was con...
متن کامل